Rethinking tire wear: Why your car's rear axle needs top treads
Which axle should have better tires installed? It might seem complex, especially given that different car models have various types of drive - front, rear, or all-wheel. However, irrespective of the drive type, the answer is unambiguous. Let us clarify.
In an ideal scenario, we would replace all the tires simultaneously. Such a procedure would be the most advantageous and eliminate any uncertainty. Unfortunately, this isn't always feasible. In modern vehicles, which typically feature front-wheel drive, the tires on the front axle wear out more rapidly.
Why does this happen? The explanation is straightforward. The front axle bears a more significant load, both statically and dynamically. This means it supports greater vehicle weight and is tasked with more functions. The front axle propels the car, steering, and brakes. Even without considering the drive, it retains two significant roles.
The front bears a heavier load in most vehicles, irrespective of road conditions. This load varies slightly, reducing somewhat during acceleration, but the balance rarely shifts to the rear axle. This is more likely in high-powered vehicles with rear-wheel drive or four-wheel drive.
Moreover, the driver can quickly increase the load on the front axle by easing off the accelerator or gently applying the brake. Hence, the front wheels’ additional "duties" are somewhat offset by better grip due to the weight distribution.
The scenario differs for the rear axle. It is less burdened statically and often lacks the capacity for additional dynamic loading. Essentially, the rear axle helps steer the vehicle around a curve. The front axle determines direction, while the rear follows it. Consequently, car manufacturers typically employ more intricate suspension systems for the rear axle.
Because it's under less strain, the rear axle is more susceptible to losing traction. For instance, abrupt braking on uneven surfaces can cause the vehicle to become unstable as the rear wheels lose grip. In turn, easing off the accelerator or even slight braking can make the rear end feel deceptively light, resulting in hazardous oversteer skidding.
Which axle should have the better tires in a car?
Therefore, the rear wheels should always ensure the best possible traction. This can be achieved in two ways: equipping them with superior tires or loading the back of the car. The latter is not always practical or feasible.
Interestingly, superior tires are often mounted on the front axle in motorsport circles, especially in rally driving. This occurs when drivers have to choose specific tires for a specific axle. For instance, when embarking on a loop (several special stages with no opportunity to return to the service area) with slick tires and two spare rain tires, the driver might opt to equip the front wheels with the better, i.e., rain tires. Why?
Because in rally racing, finishing time takes precedence over safety. With such a strategy, the car has significantly improved braking capability. Should the rear axle skid, a driver can counter the technical shortcomings with exceptional skills.
